It can be a struggle as a gardener to find something that will do the job, while also being environmentally conscious. It is so important to protect pollinators in our gardens, but that is hard to match against pests destroying plants year after year.

Frass is the answer you have been looking for: a fertiliser, a pest repellent, all while being organic and protecting pollinators.



Frass is the co-product of farming Black Soldier Flies. We feed our lovely larvae on food waste that would otherwise be headed to the landfill, and when they are all grown up they are sold as a calcium-rich feed for animals. What is left over is called frass.  It is made of the skin casings and droppings from our larvae, which we then sterilise and refine into the frass powder we sell. 

It is great for the environment because it is actively helping reduce landfill and food waste, which would otherwise be contributing to climate warming. But also by choosing frass instead of other carbon-intensive or petrochemical fertilisers, you avoid the pollution and environmental damage they cause.

Frass is a sustainable choice and it always will be.


AN ORGANIC Fertiliser

Frass has every nutritional component a plant needs for healthy growth and is rich in carbon, nitrogen, phosphorus and potassium. Frass is uniquely good at fertilising plants in the long term due to its chemical breakdown:

  • The skin casings in frass are made from chitin (14% of frass by weight), which is rich in nitrogen, phosphate and potassium - all key for growing plants. As they bind within chitin, nutrients are slowly released - not washed away by the rain. 

  • Chitin also binds to soil nutrients essential for plant growth like iron, calcium, magnesium and zinc, making them accessible to the plant. Frass is rich in a range of nutrients and has an NPK of 3 2 5.

  • The breakdown of chitin also both stimulates and fertilises the microbiome of bacteria present in the soil. This results in unprecedented increases in carbon and nitrogen mineralisation, locking carbon into the soil and increasing nutrient availability for crops. 



As chitin is also found in insects, plants mistake the high chitin content of frass as a warning of insect attack. This acts much likes a vaccination, up-regulating plant defences, making them stronger and less palatable to pests - like aphids, slugs and snails. These same mechanisms have effectiveness at reducing plant disease also, as chitin is also present in fungal pathogens like blights, rusts and mildews. The results of these defence mechanisms vary species to species but have been widely seen to include bushier growth, and earlier blooming and fruiting. 

Frass is a great alternative to pesticides as it deters insect damage, while still supporting key pollinators, likes bees and butterflies. 
Because frass does nothing but boost the natural immune system of your plant, it is both organic and completely natural. We believe that you do not need artificial pesticides - your plant already has everything it needs, all we do is give it a shove in the right direction.


If you would like to buy some frass for yourself please click HERE.

For a free application guide to using frass please click get in touch HERE.

Frass is not only excellent as a home gardening aid but has been shown in trials to be commercially viable. For more information and an application guide for agricultural uses of frass, please get in touch HERE.